A ship screw, pump screw or turbine screw for use under water or another liquid, comprising a front side and a rear side, wherein water or another liquid is forced from the front side to the rear side in use, and comprising a hub and at least two blades extending from said hub, wherein the blades are substantially helical/spiral shaped, their effective surface area increasing from the front side toward the rear side.

A motion-state dependent method for operating a kinetic generator on a marine vessels or platform includes determining a motion state of the marine vessels or platform, and imposing a limit on at least one of charging and discharging of the kinetic generator based upon the motion state to keep the kinetic generator within a safe operating range.

Systems, methods, and computer program products for monitoring a wind turbine (10). The system receives a signal (426) indicative of a pitch force being applied to a blade (20) of a wind turbine (10). The signal (426) is sampled to generate a discrete time-domain signal (426) including a plurality of pitch force samples. Samples are selected for analysis using a sampling window (326) that excludes samples obtained under operating conditions determined to be detrimental to obtaining good data. The selected samples are processed to generate a spectral density (150) of the signal (426), and the frequency content of the spectral density (150) analysed to determine the condition of one or more components of the wind turbine (10). If the analysis indicates that a component of the wind turbine (10) needs attention, the system generates an alarm.

A ship screw, pump screw or turbine screw for use under water or another liquid, comprising a front side and a rear side, wherein water or another liquid is forced from the front side to the rear side in use, and comprising a hub and at least two blades extending from said hub, wherein the blades are substantially helical/spiral shaped, their effective surface area increasing from the front side toward the rear side.

A ship screw, pump screw or turbine screw for use under water or another liquid, comprising a front side and a rear side, wherein water or another liquid is forced from the front side to the rear side in use, and comprising a hub and at least two blades extending from said hub, wherein the blades are substantially helical/spiral shaped, their effective surface area increasing from the front side toward the rear side.

A method and device for displaying computer content associated with a propulsion system, include: a standalone computer element (MO), the computer element including a display screen (4) in particular for displaying the computer content; a standalone propulsion element (PO) for moving an operator; an element for securing the computer element to the propulsion element; and an element for modifying the display of the computer content according to the movement of the operator, given that the movement of the operator takes place in a sub-aquatic environment.

A method and device for displaying computer content associated with a propulsion system, include: a standalone computer element (MO), the computer element including a display screen (4) in particular for displaying the computer content; a standalone propulsion element (PO) for moving an operator; an element for securing the computer element to the propulsion element; and an element for modifying the display of the computer content according to the movement of the operator, given that the movement of the operator takes place in a sub-aquatic environment.